Biomaterials have a long and successful history in dental and bone restoration, but the current technology is imperfect. Three-dimensional, biomineralized templates are a necessary component of bone and dental tissue engineering strategies, but methods do not yet exist for controlling the formation of biomineralized substrates with chemical and physical features that promote cell integration and function. We will first fabricate two-dimensional substrates in which macromolecules with functional groups that appear during tooth and bone formation will be micropatterned to regulate calcium phosphate crystal nucleation and growth. A constant composition method will be used to mineralize the patterned surfaces with specific chemical composition and crystalline phase. In addition, three-dimensional matrices with micropatterns will be fabricated using natural ECM proteins or synthetic polymers in a silicon mold. The patterned hydrogel matrices will be mineralized in a controlled manner using a modified constant composition method and microfluidics. Mineralized structures will be extensively characterized for chemistry, crystal structure, and topography. The controlled microstructures will be used to study the interaction between cells and the extracellular environment. Experiments will focus on the effect of the mineralized material on cell behavior; the influence of chemistry and geometry on the attachment, migration, and specific functions of cells will be studied. Together, these studies will provide new insight on the interactions between cells and substrates that occur during biomineralization. Since precisely designed synthetic materials will be produced and characterized to meet the study objectives, this project will also lead to new approaches for engineering of dental and orthopedic tissue.